I'm paranoid. Help.

[DVDdoug]

Lossy compression can be tricky... It's all about human perception...

The only way to compare is by listening. Hydrogen audio has information and links to software for doing Scientific Blind ABX Listening Tests yourself on your computer.

The most important things are:
- The bitrate/quality seting
- The musical content (Some sounds are easier to compress than others.)
- Your ability ot hear compression artifacts.

It turns-out that the playback equipment is not that important. If you can hear compression artifacts on a super high-end system, you can hear them them on an average system.

At high-bitrate/high-quality settings, most music will sound identical to the uncompressed original, and it usually won't matter what format or what encoder you use. At lower bitrates (more compression = smaller files) you may find that one format or one encoder is better than another. Or, with some some music you may get better sound quality with AAC than MP3, etc.

[Shaky]

Lossy compression can be tricky... It's all about human perception...

. . . At high-bitrate/high-quality settings, most music will sound identical to the uncompressed original, and it usually won't matter what format or what encoder you use.

You are a very knowledgeable poster and you hedge your comments somewhat, but in my view insufficiently so.

Clearly you can go into the Audacity editor and start chopping away samples randomly, and if only the slightest modicum of care is taken it will be impossible to discern for the majority of listeners.

Real, actual information/data will nevertheless be lost.

And one example that instantly springs to mind where this practice has a nasty habit of biting you in the ass is for DJs, of which there are quite a few around; Pitch down tracks in a lossy format and already somewhat thin sound with more than likely turn to crap.

ABX testing in Foobar will not reveal that, however.

[kozikowski]

Which snaps us back to the idea that MP3 is a delivery format for your iPod, not work suitable for production. MP3 (and others) work by very cleverly hiding the damage. Post production pulls back the curtain. Koz